Like the YZ450F before it, the WR450F may be too serious for some riders. This engine makes a lot of power, and even with the exhaust meeting (barely) the 96-decibel level California requires, it can be a handful when the power hits. With the plugged-up exhaust, the power is a little soft off the bottom, but as the revs climb, the power builds suddenly and is a bit of a handful in slippery conditions. Now, compared to the YZ450, the WR is a model citizen. The engine will pull at very low rpm, has, oh, 90 percent less tendency to stall and is much more tractable
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